1. Field of the Invention
The present invention relates to an anti-springback technique for increasing the densities achievable in a container by a compacting press.
2. Description of the Prior Art
When compacting material such as low level radioactive waste in a container, it is desirable to indefinitely leave the material in the container. Typically this type of waste has been placed in 55 gallon barrels and buried underground. The cost for burying such material is a function primarily of the volume and it becomes advantageous to achieve a high final compacted density. Recently, several manufacturers have developed box type containers for this purpose that enable a larger amount of waste to be more easily handled.
A problem arises when the compaction force is removed in that the material springs out of the container limiting the final compacted density. This becomes more of a problem when the compaction pressure is increased. One solution has been to place a thin sheet metal disk in a 55 gallon barrel during the final press compaction stroke. The disk will tend to be restrained by the inner sides of the barrel and will hold a light springback pressure.
When using large box type compactors the disk technique is not feasible. Using the container lid on the last stroke to press the material in the box becomes cumbersome and the pressure is limited to what the lid will withstand. U.S. Pat. No. 4,426,927 offers a holddown having pivotally connected members which can be rotated in place but is also cumbersome to insert and is limited to low pressures.
The present invention offers improvements in that it is easily snapped into place and can be made of sufficient strength to support higher springback pressures.